The wet treatment of the semiconductor surface aims for film removal, substrate etching, substrate wet doping, surface polishing, contamination removal, surface conditioning and combination of thereof. Phosphoric acid etching is a well-established process (e.g., treating wafers on wet benches). Known processes employ stable operating conditions such as acid boiling points. These processes provide good selectivity of nitride to oxide (35:1 at 165 Centigrade), which can be improved by using in addition to phosphoric acid, sulfuric acid and/or water. Use of sulfuric acid can improve the selectivity to etch nitride to oxide, while the use of water increases the silicon nitride etch rate. However, long over-etch times are sometimes needed to guarantee complete film removal, resulting in reduced throughput and high selectivity to other materials is required due to over-etch. Improvements to wet etching of semiconductor surfaces are highly sought.